The present invention relates to a recording apparatus, and more particularly to a device for detecting the time instant that the ink has been nearly used up in a recording apparatus (hereinafter referred to as "an ink near-end detecting device", when applicable).
When, in an ink jet type recording apparatus in which ink is ejected from the nozzles to record data on a recording medium, the ink in the ink tank is used up, of course it is impossible to continue the recording operation. If the ink supply is entirely depleted, air can pass into the passageways connecting the ink supply to the nozzle. As a result, it takes a considerably long period of time to start the recording operation again.
The difficulty can be overcome by providing a detector for detecting the ink level in the ink tank. However, this approach is not applicable to a recording apparatus in which the ink tank is mounted on a movable carriage. In such an apparatus, it is generally the practice apparatus to accommodate a porous material in the ink tank to hold the ink, thereby to prevent the entrance of bubbles into the passageways connecting the ink supply to the nozzles, which bubbles are formed by vibration caused when the carriage is returned. Accordingly, it is impossible for the detector to directly detect the time instant immediately before the ink is used up.